In the oil and gas industry throughout the world, hydrocarbon fluids, natural gas and methane are conveyed through transmission pipeline systems. The majority of such pipelines are manufactured with ferrous steel. Black powder is a problem with these oil and gas pipelines. These pipelines typically wear from the inside from corrosion and erosion and the operational life of a pipeline is directly correlated to the quality of the iron used and the quality of the manufacturing process. This corrosion and erosion causes the formation of black powder in the pipeline. Black powder typically consists of various forms of iron sulfide and/or iron oxide and can also consist of some portion of silica dust and other materials. The higher the quality of material and production capability the longer the pipeline will last. Lower grade material and production will result in higher amounts of black power forming and significantly reduced operational life.
Pipeline erosion is a serious problem. Some main causes of pipeline erosion include: the flow of gas or hydro carbon fluids creates friction through contact resulting in very fine particles (the black powder) down to and below 10 microns in size to be eroded from the pipe wall, then enter and suspend in the flow; the increase of the ferrous contamination (black powder) levels as the gas or hydrocarbon fluid travels along the pipeline system are directly correlated with the distance traveled and pipe quality; as the level of ferrous contamination suspended in the gas and or hydrocarbon fluid increases the opportunity and ability to erode the pipe wall increases significantly, which is due to the hardness factor of the ferrous contamination suspended in the flow.
Corrosion is another serious problem for pipelines. Moisture will accumulate as the temperature and humidity rise and fall. The moisture will oxidize the ferrous metal creating scaling on the surface of the pipe wall. The flow of the gas or hydrocarbon fluids break away the scale with the assistance of the fine ferrous contamination already suspended in the flow forming black powder traveling through the pipeline.
Again, the mitigating factor to the wear ratio is the quality of pipe and the distance traveled and the ferrous and non ferrous (silica sand) contamination suspended in the flow.
The ferrous contamination (black powder) created by the transmission process creates additional serious operational problems with the process of transporting the gas or hydrocarbon fluid though the transmission line and can directly affect the quality of the medium flowing through the pipeline A number of problems can arise from ferrous contamination: the gas and or hydrocarbon fluid quality can be degraded due to the level of ferrous contamination; the ferrous contamination can prematurely wear the meter gauges and in some cases plug the meter creating a serious issue of flow volume accuracy; the fine ferrous contamination can enter and settle in the flow control valves causing them to fail; the ferrous metal can prematurely wear pump, compressor and turbine components along the transmission lines; the ferrous metal contamination can cause a multitude of problems when the gas and or hydrocarbon fluid enters the refining process from pump and pipe wear to contamination of the by-product separation and production processes; and when the gas or hydrocarbon fluid is warehoused in ferrous steel reservoirs, it again is subject to ferrous metal contamination from corrosion.
One solution is to remove the ferrous contamination from as many opportune locations as possible along the pipeline system to reduce the accumulating negative impact it has on the pipeline, associated rotating equipment and metering gauges. However, traditional filtration technology, such as cyclone or centrifuge filters and media filters employed to date have proven to be expensive. They can also be inefficient and create flow restrictions. In some cases they can even collapse from back pressure created when they become plugged.